//
//  main.cpp
//  bg
//
//  Created by Qing Liu on 15/11/3.
//  Copyright © 2015年 Qing Liu. All rights reserved.
//

#include <iostream>
#include <algorithm>
#include <cstdio>
#include <vector>
#include <cmath>
#include <queue>
#include <cstring>
#define inf 999999999
#define maxn 300000
using namespace std;
int a[maxn];
struct edge{
    int to,cap,rev;
};
vector<edge>G[maxn];
void addedge(int from,int to,int cap){
    G[from].push_back((edge){to,cap,(int)G[to].size()});
    G[to].push_back((edge){from,0,(int)G[from].size()-1});
}
int level[maxn],ltr[maxn];
void BFS(int s){
    queue<int>que;
    que.push(s);
    memset(level, -1, sizeof(level));
    level[s]=0;
    while (!que.empty()) {
        int k=que.front();
        que.pop();
        for (int i=0; i<G[k].size(); i++) {
            edge &e=G[k][i];
            if (level[e.to]==-1&&e.cap>0) {
                level[e.to]=level[k]+1;
                que.push(e.to);
            }
        }
    }
}
int DFS(int s,int t,int f){
    if(s==t){
        return f;
    }
    for (int &i=ltr[s]; i<G[s].size(); i++) {
        edge &e=G[s][i];
        if (level[e.to]>level[s]&&e.cap>0) {
            int d=DFS(e.to, t, min(e.cap,f));
            if (d>0) {
                e.cap-=d;
                G[e.to][e.rev].cap+=d;
                return d;
            }
        }
    }
    return 0;
}
int max_flow(int s,int t){
    int ans=0;
    BFS(s);
    while (level[t]>0) {
        memset(ltr, 0, sizeof(ltr));
        int f=DFS(s, t, inf);
        while (f>0) {
            ans+=f;
            f=DFS(s, t, inf);
        }
        BFS(s);
    }
    return ans;
}
int main() {
    freopen("bg.in", "r", stdin);
    freopen("bg.out", "w", stdout);
    int m,n;
    cin>>m>>n;
    for (int i=1; i<=m;i++ ) {
        int temp;
        cin>>temp;
        a[i]=temp;
        addedge(0, i, 1);
    }
    sort(a+1, a+m+1);
    for (int i=1; i<=n; i++) {
        addedge(i+m, 210000, 1);
        int l,r;
        cin>>l>>r;
        int k=lower_bound(a+1, a+m+1, l)-a;
        for (int j=k; j<=n; j++) {
            if (a[j]>r) {
                break;
            }
            addedge(j, i+m, 1);
        }
    }
    cout<<max_flow(0, 210000);
    return 0;
}